<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .box {
        margin: 0 auto;
        width: 600px;
        height: 400px;
        border: 10px dashed #fca;
        position: relative;
      }
      .box::before {
        content: "";
        position: absolute;
        width: 100%;
        height: 100%;
        clip-path: circle(30px at 0 0);
        background-color: skyblue;
        transition: all linear 2s;
      }
      .box::after {
        content: "";
        position: absolute;
        width: 100%;
        height: 100%;
        clip-path: circle(30px at bottom right);
        background-color: #caf;
        transition: all linear 2s;
      }
      .box:hover::after {
        clip-path: circle(500px at bottom right);
      }
      .box:hover::before {
        clip-path: circle(500px at 0 0);
      }
    </style>
  </head>
  <body>
    <div class="box"></div>
  </body>
</html>

